摘要
HZSM-5/Al2O3催化剂比表面积较大,催化剂表面上B酸中心和L酸中心共存,且弱酸中心密度高于强酸中心密度。加氢裂化尾油非临氢降凝反应是正碳离子反应机理,但弱酸强度催化剂不利于正碳离子的生成,使催化降凝效果受到限制。通过在原料中加入醇类链转移剂(异丙醇、正丁醇、异丁醇和叔丁醇)促进正碳离子的生成,使催化降凝白油产品收率得到提高,质量得以改善。这些醇类链转移剂中,叔丁醇更易生成稳定的正碳离子,所得液体产品白油收率最高,性质比较稳定,能够满足工厂产品质量要求,是较好的加氢裂化尾油非临氢降凝的链转移剂。
HZSM-5/Al2O3 catalyst attracts great interest due to its larger specific surface area, B acid center and L acid center coexisting on the surface of the catalyst and the higher weak acid center density. Non-hydro-dewaxing reaction of hydrocracking tail oil is found to undergo carbonium ion reaction mechanism. However, this weak acid catalyst is not conducive to the formation of carbocations, which greatly decreases the catalytic dewaxing effect. In this study, by adding isopropyl alcohol, butyl alcohol,isobutyl alcohol and tert-butyl alcohol （TBA） in the raw material as the chain transfer agents to accelerate the formation of carbonium ion, the improved yield and properties of white oil can be achieved. In particular,the obtained white oil with TBA as chain transfer agent has the highest yield and good stability, which is attributed to the more easily generated carbonium ion of TBA than other alcohols. TBA is the best chain transfer agent for non-hydro-dewaxing of hydrocracking tail oil.
出处
《现代化工》
CAS
CSCD
北大核心
2015年第7期78-81,共4页
Modern Chemical Industry
关键词
表征
加氢裂化尾油
链转移剂
白油
性质
characterization
hydrocracking tail oil
chain transfer agents
white oil
properties
